�ݺ�ߣshows by User: RajKumar1819

�ݺ�ߣshows by User: RajKumar1819 / http://www.slideshare.net/images/logo.gif �ݺ�ߣshows by User: RajKumar1819 / Tue, 26 Apr 2022 14:04:09 GMT �ݺ�ߣShare feed for �ݺ�ߣshows by User: RajKumar1819 Muscle Tissue Types and Functions.pptx /slideshow/muscle-tissue-types-and-functionspptx/251668983 muscletissuetypesandfunctions-220426140410
Muscle tissue is composed of cells that have the ability to shorten or contract in order to produce movement of the body parts Properties of Muscular Tissue Contractibility – Ability of muscle cells to shorten Excitability – Muscle tissue responds to a stimulus delivered from neuron or hormone Extensibility – Ability to be stretched Elasticity – Ability to recoil back to its original length after being stretched Structure of Muscular tissue Muscular tissues are bundled together and surrounded by tough connective tissue known as epimysium The tissue made of many muscle fibres (myocytes) Fascicles are surrounded by a protective layer known as perimysium Muscle fibres are composed of numerous fine myofibrils Muscle fibres can contract and relax Muscles take part in locomotion and movements 1. Skeletal muscle Skeletal muscles are attached to the skeleton They are also known as striated muscles because of the presence of alternate patterns of light and dark bands These light and dark bands are highly organized structures of actin, myosin, and proteins. These add to the contractility and extensibility of the muscles Skeletal muscles are also known as voluntary muscles Skeletal muscle tissue is composed of long cells called muscle fibers that have multinucleated They play a vital role in everyday activities 2. Smooth muscle These muscle cells are spindle-shaped with a single nucleus Smooth muscle is found in the walls of hollow organs throughout the body These are non-striated, involuntary muscles controlled by nervous system The actin and myosin filaments are very thin and arranged randomly, hence no striations It stimulates the contractility of the digestive, urinary, reproductive systems and blood vessels 3. Cardiac Muscle Tissue Cardiac muscle tissue is present only in the heart They are single celled and uninucleated The cells of the cardiac muscles known as the cardiomyocytes are striated These are involuntary muscles and the heart pumps the blood through cardiac contractions Muscle cells, unique junctions called intercalated discs (gap junctions) Intercalated discs are the major portal for cardiac cell to cell communication ]]>
Muscle tissue is composed of cells that have the ability to shorten or contract in order to produce movement of the body parts Properties of Muscular Tissue Contractibility – Ability of muscle cells to shorten Excitability – Muscle tissue responds to a stimulus delivered from neuron or hormone Extensibility – Ability to be stretched Elasticity – Ability to recoil back to its original length after being stretched Structure of Muscular tissue Muscular tissues are bundled together and surrounded by tough connective tissue known as epimysium The tissue made of many muscle fibres (myocytes) Fascicles are surrounded by a protective layer known as perimysium Muscle fibres are composed of numerous fine myofibrils Muscle fibres can contract and relax Muscles take part in locomotion and movements 1. Skeletal muscle Skeletal muscles are attached to the skeleton They are also known as striated muscles because of the presence of alternate patterns of light and dark bands These light and dark bands are highly organized structures of actin, myosin, and proteins. These add to the contractility and extensibility of the muscles Skeletal muscles are also known as voluntary muscles Skeletal muscle tissue is composed of long cells called muscle fibers that have multinucleated They play a vital role in everyday activities 2. Smooth muscle These muscle cells are spindle-shaped with a single nucleus Smooth muscle is found in the walls of hollow organs throughout the body These are non-striated, involuntary muscles controlled by nervous system The actin and myosin filaments are very thin and arranged randomly, hence no striations It stimulates the contractility of the digestive, urinary, reproductive systems and blood vessels 3. Cardiac Muscle Tissue Cardiac muscle tissue is present only in the heart They are single celled and uninucleated The cells of the cardiac muscles known as the cardiomyocytes are striated These are involuntary muscles and the heart pumps the blood through cardiac contractions Muscle cells, unique junctions called intercalated discs (gap junctions) Intercalated discs are the major portal for cardiac cell to cell communication ]]> Tue, 26 Apr 2022 14:04:09 GMT /slideshow/muscle-tissue-types-and-functionspptx/251668983 RajKumar1819@slideshare.net(RajKumar1819) Muscle Tissue Types and Functions.pptx RajKumar1819 Muscle tissue is composed of cells that have the ability to shorten or contract in order to produce movement of the body parts Properties of Muscular Tissue Contractibility – Ability of muscle cells to shorten Excitability – Muscle tissue responds to a stimulus delivered from neuron or hormone Extensibility – Ability to be stretched Elasticity – Ability to recoil back to its original length after being stretched Structure of Muscular tissue Muscular tissues are bundled together and surrounded by tough connective tissue known as epimysium The tissue made of many muscle fibres (myocytes) Fascicles are surrounded by a protective layer known as perimysium Muscle fibres are composed of numerous fine myofibrils Muscle fibres can contract and relax Muscles take part in locomotion and movements 1. Skeletal muscle Skeletal muscles are attached to the skeleton They are also known as striated muscles because of the presence of alternate patterns of light and dark bands These light and dark bands are highly organized structures of actin, myosin, and proteins. These add to the contractility and extensibility of the muscles Skeletal muscles are also known as voluntary muscles Skeletal muscle tissue is composed of long cells called muscle fibers that have multinucleated They play a vital role in everyday activities 2. Smooth muscle These muscle cells are spindle-shaped with a single nucleus Smooth muscle is found in the walls of hollow organs throughout the body These are non-striated, involuntary muscles controlled by nervous system The actin and myosin filaments are very thin and arranged randomly, hence no striations It stimulates the contractility of the digestive, urinary, reproductive systems and blood vessels 3. Cardiac Muscle Tissue Cardiac muscle tissue is present only in the heart They are single celled and uninucleated The cells of the cardiac muscles known as the cardiomyocytes are striated These are involuntary muscles and the heart pumps the blood through cardiac contractions Muscle cells, unique junctions called intercalated discs (gap junctions) Intercalated discs are the major portal for cardiac cell to cell communication <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/muscletissuetypesandfunctions-220426140410-thumbnail.jpg?width=120&height=120&fit=bounds" /><br> Muscle tissue is composed of cells that have the ability to shorten or contract in order to produce movement of the body parts Properties of Muscular Tissue Contractibility – Ability of muscle cells to shorten Excitability – Muscle tissue responds to a stimulus delivered from neuron or hormone Extensibility – Ability to be stretched Elasticity – Ability to recoil back to its original length after being stretched Structure of Muscular tissue Muscular tissues are bundled together and surrounded by tough connective tissue known as epimysium The tissue made of many muscle fibres (myocytes) Fascicles are surrounded by a protective layer known as perimysium Muscle fibres are composed of numerous fine myofibrils Muscle fibres can contract and relax Muscles take part in locomotion and movements 1. Skeletal muscle Skeletal muscles are attached to the skeleton They are also known as striated muscles because of the presence of alternate patterns of light and dark bands These light and dark bands are highly organized structures of actin, myosin, and proteins. These add to the contractility and extensibility of the muscles Skeletal muscles are also known as voluntary muscles Skeletal muscle tissue is composed of long cells called muscle fibers that have multinucleated They play a vital role in everyday activities 2. Smooth muscle These muscle cells are spindle-shaped with a single nucleus Smooth muscle is found in the walls of hollow organs throughout the body These are non-striated, involuntary muscles controlled by nervous system The actin and myosin filaments are very thin and arranged randomly, hence no striations It stimulates the contractility of the digestive, urinary, reproductive systems and blood vessels 3. Cardiac Muscle Tissue Cardiac muscle tissue is present only in the heart They are single celled and uninucleated The cells of the cardiac muscles known as the cardiomyocytes are striated These are involuntary muscles and the heart pumps the blood through cardiac contractions Muscle cells, unique junctions called intercalated discs (gap junctions) Intercalated discs are the major portal for cardiac cell to cell communication

Muscle Tissue Types and Functions.pptx from Raj Kumar

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0 Continental Drift Theory by Rajkumar /slideshow/continental-drift-theory-by-rajkumar/127164776 continentaldrift-190102165106
1. CONTINENTAL DRIFT “Father” of this theory is Alfred Wegener. 2. The Theory of Continental Drift Proposed by Alfred Wegener (1912):- A large super-continent PANGEA split into smaller fragments about 200-300 million years ago. These then drifted apart to form the present arrangement of continents. Most geologists were highly skeptical and the idea was NOT widely accepted. 3. This is what Wegener thought Pangea looked like 200-300 million years ago. 4. EVIDENCE OF CONTINENTAL DRIFT Wegener provided four main pieces of evidence to support his theory that the continents had been drifting over time. 5. 1. JIGSAW PUZZLE Wegener noticed that if we could move present day continents around, several continents look like they would fit together like pieces of a jigsaw puzzle. 6. 2. FOSSILS Wegener also found fossils of the same plants and animals on different continents now separated by vast oceans. They could only be found this way if the continents had once been joined together. 7. 3. ROCK SEQUENCE Wegener also found that mountain ranges have a similar sequence of type of rock and age on both sides of the Atlantic Ocean, suggesting they were once part of the same mountain range. 8. 4. GLACIAL SCARS Wegener found evidence of glacial scars left behind by giant ice sheets from the same time period in Southern Africa, India, Australia and South America. The white areas were covered by ice and tundra about 300 million years ago (arrows show the direction of ice movement). the continents were once part of a single larger continent that then split apart, drifting to their present positions over the last 300 million years. 9. WHAT COULD MOVE THE CONTINENTS? Unfortunately for Wegener, he could not explain what force was powerful enough to move entire continents around the planet. For reasons was he can't explain Alfred Wegener died on expedition in Greenland in 1930 still searching for answers to the question of what force could be responsible for the movement of the continents. 10. Reason for Support Continental Drift? Fit of continents Apparent discrepancy in inferred latitudes of ancient rocks Rocks of same age and similar characteristics on different continents Distribution of similar plants and animals on different continents 11. WEGENERS CONCLUSIONS: The continents have drifted over the past 300 million years to their present positions! (not a very popular idea at the time!!!)]]>
1. CONTINENTAL DRIFT “Father” of this theory is Alfred Wegener. 2. The Theory of Continental Drift Proposed by Alfred Wegener (1912):- A large super-continent PANGEA split into smaller fragments about 200-300 million years ago. These then drifted apart to form the present arrangement of continents. Most geologists were highly skeptical and the idea was NOT widely accepted. 3. This is what Wegener thought Pangea looked like 200-300 million years ago. 4. EVIDENCE OF CONTINENTAL DRIFT Wegener provided four main pieces of evidence to support his theory that the continents had been drifting over time. 5. 1. JIGSAW PUZZLE Wegener noticed that if we could move present day continents around, several continents look like they would fit together like pieces of a jigsaw puzzle. 6. 2. FOSSILS Wegener also found fossils of the same plants and animals on different continents now separated by vast oceans. They could only be found this way if the continents had once been joined together. 7. 3. ROCK SEQUENCE Wegener also found that mountain ranges have a similar sequence of type of rock and age on both sides of the Atlantic Ocean, suggesting they were once part of the same mountain range. 8. 4. GLACIAL SCARS Wegener found evidence of glacial scars left behind by giant ice sheets from the same time period in Southern Africa, India, Australia and South America. The white areas were covered by ice and tundra about 300 million years ago (arrows show the direction of ice movement). the continents were once part of a single larger continent that then split apart, drifting to their present positions over the last 300 million years. 9. WHAT COULD MOVE THE CONTINENTS? Unfortunately for Wegener, he could not explain what force was powerful enough to move entire continents around the planet. For reasons was he can't explain Alfred Wegener died on expedition in Greenland in 1930 still searching for answers to the question of what force could be responsible for the movement of the continents. 10. Reason for Support Continental Drift? Fit of continents Apparent discrepancy in inferred latitudes of ancient rocks Rocks of same age and similar characteristics on different continents Distribution of similar plants and animals on different continents 11. WEGENERS CONCLUSIONS: The continents have drifted over the past 300 million years to their present positions! (not a very popular idea at the time!!!)]]> Wed, 02 Jan 2019 16:51:06 GMT /slideshow/continental-drift-theory-by-rajkumar/127164776 RajKumar1819@slideshare.net(RajKumar1819) Continental Drift Theory by Rajkumar RajKumar1819 1. CONTINENTAL DRIFT “Father” of this theory is Alfred Wegener. 2. The Theory of Continental Drift Proposed by Alfred Wegener (1912):- A large super-continent PANGEA split into smaller fragments about 200-300 million years ago. These then drifted apart to form the present arrangement of continents. Most geologists were highly skeptical and the idea was NOT widely accepted. 3. This is what Wegener thought Pangea looked like 200-300 million years ago. 4. EVIDENCE OF CONTINENTAL DRIFT Wegener provided four main pieces of evidence to support his theory that the continents had been drifting over time. 5. 1. JIGSAW PUZZLE Wegener noticed that if we could move present day continents around, several continents look like they would fit together like pieces of a jigsaw puzzle. 6. 2. FOSSILS Wegener also found fossils of the same plants and animals on different continents now separated by vast oceans. They could only be found this way if the continents had once been joined together. 7. 3. ROCK SEQUENCE Wegener also found that mountain ranges have a similar sequence of type of rock and age on both sides of the Atlantic Ocean, suggesting they were once part of the same mountain range. 8. 4. GLACIAL SCARS Wegener found evidence of glacial scars left behind by giant ice sheets from the same time period in Southern Africa, India, Australia and South America. The white areas were covered by ice and tundra about 300 million years ago (arrows show the direction of ice movement). the continents were once part of a single larger continent that then split apart, drifting to their present positions over the last 300 million years. 9. WHAT COULD MOVE THE CONTINENTS? Unfortunately for Wegener, he could not explain what force was powerful enough to move entire continents around the planet. For reasons was he can't explain Alfred Wegener died on expedition in Greenland in 1930 still searching for answers to the question of what force could be responsible for the movement of the continents. 10. Reason for Support Continental Drift? Fit of continents Apparent discrepancy in inferred latitudes of ancient rocks Rocks of same age and similar characteristics on different continents Distribution of similar plants and animals on different continents 11. WEGENERS CONCLUSIONS: The continents have drifted over the past 300 million years to their present positions! (not a very popular idea at the time!!!) <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/continentaldrift-190102165106-thumbnail.jpg?width=120&height=120&fit=bounds" /><br> 1. CONTINENTAL DRIFT “Father” of this theory is Alfred Wegener. 2. The Theory of Continental Drift Proposed by Alfred Wegener (1912):- A large super-continent PANGEA split into smaller fragments about 200-300 million years ago. These then drifted apart to form the present arrangement of continents. Most geologists were highly skeptical and the idea was NOT widely accepted. 3. This is what Wegener thought Pangea looked like 200-300 million years ago. 4. EVIDENCE OF CONTINENTAL DRIFT Wegener provided four main pieces of evidence to support his theory that the continents had been drifting over time. 5. 1. JIGSAW PUZZLE Wegener noticed that if we could move present day continents around, several continents look like they would fit together like pieces of a jigsaw puzzle. 6. 2. FOSSILS Wegener also found fossils of the same plants and animals on different continents now separated by vast oceans. They could only be found this way if the continents had once been joined together. 7. 3. ROCK SEQUENCE Wegener also found that mountain ranges have a similar sequence of type of rock and age on both sides of the Atlantic Ocean, suggesting they were once part of the same mountain range. 8. 4. GLACIAL SCARS Wegener found evidence of glacial scars left behind by giant ice sheets from the same time period in Southern Africa, India, Australia and South America. The white areas were covered by ice and tundra about 300 million years ago (arrows show the direction of ice movement). the continents were once part of a single larger continent that then split apart, drifting to their present positions over the last 300 million years. 9. WHAT COULD MOVE THE CONTINENTS? Unfortunately for Wegener, he could not explain what force was powerful enough to move entire continents around the planet. For reasons was he can't explain Alfred Wegener died on expedition in Greenland in 1930 still searching for answers to the question of what force could be responsible for the movement of the continents. 10. Reason for Support Continental Drift? Fit of continents Apparent discrepancy in inferred latitudes of ancient rocks Rocks of same age and similar characteristics on different continents Distribution of similar plants and animals on different continents 11. WEGENERS CONCLUSIONS: The continents have drifted over the past 300 million years to their present positions! (not a very popular idea at the time!!!)

Continental Drift Theory by Rajkumar from Raj Kumar

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0 Female gametophytes - Embryology /slideshow/female-gametophytes-embryology/127097800 femalegametophytes-190101155155
1. INTRODUCTION A gametophyte is a stage in the life cycle of plants and algae that undergo alternation of generations. The gametophyte is the sexual phase in the life cycle of plants and algae. Cell division of the zygote results in a new diploid multicellular organism, the second stage in the life cycle known as the sporophyte, the function of which is to produce haploid spores by meiosis. 2. Structure of Female Gametophyte The female gametophyte is also called the embryo sac. In angiosperms it mostly develops as a seven celled, eight-nucleate structure. It consists of three antipodal cells, one central cell, two synergid cells, and one egg cell mostly. 3.Structure of Female Gametophyte It generally contain antipodal cells at chalazal ends, an egg cell and two synergids at microplyar ends, and a center containing two polar nuclei. Embryo sec is expect the center binucleate cell. The process of formation of embryo sac is known as megasporogenesis. 4.The female gametophyte first arise as a tiny protuberance from the placenta, in the cavity of the overy. As it mature,the ovule consists of a nutritive cellular mass known as nucellus, protected by two integuments, and attached to the placenta by a funiculus. Even at an early stage, one cell becomes evident in the nucellus, which is known as the megaspore mother cell(MMC). 5.MMC is diploid (2n) The MMC then increases in size, and divides twice (meiotically) to from 4 megaspore as ‘linear tetrad’ The first division is a reduction division The resultant megaspores are haploid (n) Out of the four megaspores, three degenerate, forming caps, while one remains functional. 6.This functionl megaspore is haploid (n) The functional megaspore, then grows rapidally, by absorbing nutrition from nucellus, and forms the embryo sac. The process of formation of embryo sac is known as megasporogenesis. The embryo sac consists of one nucleus. The nucleus divided into two daughter nuclei, which move towards the poles. The pole of the embryo sac, closer to the chalaza, is the chalazal end,and the one closer to the microphyle is the micropylar end. 7.Each daughter nuclei divides again, and result in four nuclei. Each nuclei divides again, for the last time, and result in eight nuclei. One nuclei from each end, come to the centre, and fuse to from a diploid secondary nucleus. The nuclei at the chalazal end, get surronded by cytoplasm, and form three distinct, haploid, antipodal cells. Similarly, the nuclei at the micropylar end, form the egg apparatus, consisting of tow haploid synergids on either side of a large, central, haploid egg cell. 8.DEVELOPMENT OF FEMALE GAMETOPHYTE PICTURE. Thank You.]]>
1. INTRODUCTION A gametophyte is a stage in the life cycle of plants and algae that undergo alternation of generations. The gametophyte is the sexual phase in the life cycle of plants and algae. Cell division of the zygote results in a new diploid multicellular organism, the second stage in the life cycle known as the sporophyte, the function of which is to produce haploid spores by meiosis. 2. Structure of Female Gametophyte The female gametophyte is also called the embryo sac. In angiosperms it mostly develops as a seven celled, eight-nucleate structure. It consists of three antipodal cells, one central cell, two synergid cells, and one egg cell mostly. 3.Structure of Female Gametophyte It generally contain antipodal cells at chalazal ends, an egg cell and two synergids at microplyar ends, and a center containing two polar nuclei. Embryo sec is expect the center binucleate cell. The process of formation of embryo sac is known as megasporogenesis. 4.The female gametophyte first arise as a tiny protuberance from the placenta, in the cavity of the overy. As it mature,the ovule consists of a nutritive cellular mass known as nucellus, protected by two integuments, and attached to the placenta by a funiculus. Even at an early stage, one cell becomes evident in the nucellus, which is known as the megaspore mother cell(MMC). 5.MMC is diploid (2n) The MMC then increases in size, and divides twice (meiotically) to from 4 megaspore as ‘linear tetrad’ The first division is a reduction division The resultant megaspores are haploid (n) Out of the four megaspores, three degenerate, forming caps, while one remains functional. 6.This functionl megaspore is haploid (n) The functional megaspore, then grows rapidally, by absorbing nutrition from nucellus, and forms the embryo sac. The process of formation of embryo sac is known as megasporogenesis. The embryo sac consists of one nucleus. The nucleus divided into two daughter nuclei, which move towards the poles. The pole of the embryo sac, closer to the chalaza, is the chalazal end,and the one closer to the microphyle is the micropylar end. 7.Each daughter nuclei divides again, and result in four nuclei. Each nuclei divides again, for the last time, and result in eight nuclei. One nuclei from each end, come to the centre, and fuse to from a diploid secondary nucleus. The nuclei at the chalazal end, get surronded by cytoplasm, and form three distinct, haploid, antipodal cells. Similarly, the nuclei at the micropylar end, form the egg apparatus, consisting of tow haploid synergids on either side of a large, central, haploid egg cell. 8.DEVELOPMENT OF FEMALE GAMETOPHYTE PICTURE. Thank You.]]> Tue, 01 Jan 2019 15:51:55 GMT /slideshow/female-gametophytes-embryology/127097800 RajKumar1819@slideshare.net(RajKumar1819) Female gametophytes - Embryology RajKumar1819 1. INTRODUCTION A gametophyte is a stage in the life cycle of plants and algae that undergo alternation of generations. The gametophyte is the sexual phase in the life cycle of plants and algae. Cell division of the zygote results in a new diploid multicellular organism, the second stage in the life cycle known as the sporophyte, the function of which is to produce haploid spores by meiosis. 2. Structure of Female Gametophyte The female gametophyte is also called the embryo sac. In angiosperms it mostly develops as a seven celled, eight-nucleate structure. It consists of three antipodal cells, one central cell, two synergid cells, and one egg cell mostly. 3.Structure of Female Gametophyte It generally contain antipodal cells at chalazal ends, an egg cell and two synergids at microplyar ends, and a center containing two polar nuclei. Embryo sec is expect the center binucleate cell. The process of formation of embryo sac is known as megasporogenesis. 4.The female gametophyte first arise as a tiny protuberance from the placenta, in the cavity of the overy. As it mature,the ovule consists of a nutritive cellular mass known as nucellus, protected by two integuments, and attached to the placenta by a funiculus. Even at an early stage, one cell becomes evident in the nucellus, which is known as the megaspore mother cell(MMC). 5.MMC is diploid (2n) The MMC then increases in size, and divides twice (meiotically) to from 4 megaspore as ‘linear tetrad’ The first division is a reduction division The resultant megaspores are haploid (n) Out of the four megaspores, three degenerate, forming caps, while one remains functional. 6.This functionl megaspore is haploid (n) The functional megaspore, then grows rapidally, by absorbing nutrition from nucellus, and forms the embryo sac. The process of formation of embryo sac is known as megasporogenesis. The embryo sac consists of one nucleus. The nucleus divided into two daughter nuclei, which move towards the poles. The pole of the embryo sac, closer to the chalaza, is the chalazal end,and the one closer to the microphyle is the micropylar end. 7.Each daughter nuclei divides again, and result in four nuclei. Each nuclei divides again, for the last time, and result in eight nuclei. One nuclei from each end, come to the centre, and fuse to from a diploid secondary nucleus. The nuclei at the chalazal end, get surronded by cytoplasm, and form three distinct, haploid, antipodal cells. Similarly, the nuclei at the micropylar end, form the egg apparatus, consisting of tow haploid synergids on either side of a large, central, haploid egg cell. 8.DEVELOPMENT OF FEMALE GAMETOPHYTE PICTURE. Thank You. <img style="border:1px solid #C3E6D8;float:right;" alt="" src="https://cdn.slidesharecdn.com/ss_thumbnails/femalegametophytes-190101155155-thumbnail.jpg?width=120&height=120&fit=bounds" /><br> 1. INTRODUCTION A gametophyte is a stage in the life cycle of plants and algae that undergo alternation of generations. The gametophyte is the sexual phase in the life cycle of plants and algae. Cell division of the zygote results in a new diploid multicellular organism, the second stage in the life cycle known as the sporophyte, the function of which is to produce haploid spores by meiosis. 2. Structure of Female Gametophyte The female gametophyte is also called the embryo sac. In angiosperms it mostly develops as a seven celled, eight-nucleate structure. It consists of three antipodal cells, one central cell, two synergid cells, and one egg cell mostly. 3.Structure of Female Gametophyte It generally contain antipodal cells at chalazal ends, an egg cell and two synergids at microplyar ends, and a center containing two polar nuclei. Embryo sec is expect the center binucleate cell. The process of formation of embryo sac is known as megasporogenesis. 4.The female gametophyte first arise as a tiny protuberance from the placenta, in the cavity of the overy. As it mature,the ovule consists of a nutritive cellular mass known as nucellus, protected by two integuments, and attached to the placenta by a funiculus. Even at an early stage, one cell becomes evident in the nucellus, which is known as the megaspore mother cell(MMC). 5.MMC is diploid (2n) The MMC then increases in size, and divides twice (meiotically) to from 4 megaspore as ‘linear tetrad’ The first division is a reduction division The resultant megaspores are haploid (n) Out of the four megaspores, three degenerate, forming caps, while one remains functional. 6.This functionl megaspore is haploid (n) The functional megaspore, then grows rapidally, by absorbing nutrition from nucellus, and forms the embryo sac. The process of formation of embryo sac is known as megasporogenesis. The embryo sac consists of one nucleus. The nucleus divided into two daughter nuclei, which move towards the poles. The pole of the embryo sac, closer to the chalaza, is the chalazal end,and the one closer to the microphyle is the micropylar end. 7.Each daughter nuclei divides again, and result in four nuclei. Each nuclei divides again, for the last time, and result in eight nuclei. One nuclei from each end, come to the centre, and fuse to from a diploid secondary nucleus. The nuclei at the chalazal end, get surronded by cytoplasm, and form three distinct, haploid, antipodal cells. Similarly, the nuclei at the micropylar end, form the egg apparatus, consisting of tow haploid synergids on either side of a large, central, haploid egg cell. 8.DEVELOPMENT OF FEMALE GAMETOPHYTE PICTURE. Thank You.

Female gametophytes - Embryology from Raj Kumar

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0 https://cdn.slidesharecdn.com/profile-photo-RajKumar1819-48x48.jpg?cb=1650981702 https://cdn.slidesharecdn.com/ss_thumbnails/muscletissuetypesandfunctions-220426140410-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/muscle-tissue-types-and-functionspptx/251668983 Muscle Tissue Types an... https://cdn.slidesharecdn.com/ss_thumbnails/continentaldrift-190102165106-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/continental-drift-theory-by-rajkumar/127164776 Continental Drift Theo... https://cdn.slidesharecdn.com/ss_thumbnails/femalegametophytes-190101155155-thumbnail.jpg?width=320&height=320&fit=bounds slideshow/female-gametophytes-embryology/127097800 Female gametophytes - ...